Soft tripping system for ship cold box load and use method thereof

Abstract

The invention relates to a ship cold box load soft tripping system and a use method thereof, the ship cold box load soft tripping system comprises a power management work station and a plurality of cold box distribution boards, the power management work station is arranged in a central control room, and at least two cold box distribution boards are arranged and are distributed in a bow area and a stern area; the power management work station comprises a main PLC module and a PC module, the main PLC module is connected with a plurality of sub-PLC modules, the sub-PLC modules are arranged in the cold box distribution board, and signals are input to the central control room power management work station through an optical fiber ring network; a power monitoring module is arranged on a cold storage distribution box supply switch in the cold box distribution board, and the power monitoring module accesses a real-time power signal to an analog quantity signal module of a PLC in the distribution board; the refrigeration distribution box supply switch is provided with an electric operation function, and control and state signals of the refrigeration distribution box supply switch are connected to the input and output module of the PLC in the electric plate. According to the method, the effects of energy conservation and emission reduction are achieved, and the grade of the carbon intensity factor CII is improved.

Description

Technical Field

[0001] The present invention relates to the field of ship electrical technology, and in particular to a soft tripping system for ship cold box load and a use method thereof. Background Art

[0002] The International Maritime Organization (IMO) continues to contribute to addressing climate change, supports the United Nations' sustainable development goals, and develops new greenhouse gas emission reduction measures, including the EU ETS (carbon trading) carbon tax system based on CII performance. CII performance refers to the carbon emission intensity of ships during operation, which is mainly measured by CII ratings. Ship energy saving, low carbon and environmental protection have become important research topics in the shipbuilding and shipping industries around the world, related to fuel and cost saving, environmental protection, and economic benefits of ship operations.

[0003] Cold box load is one of the most important research objects. When the grid power reaches the set value, large container ships start the standby generator and connect to the grid to meet the load requirements. In order to ensure that the ship does not lose power under various working conditions, large container ships directly disconnect the cold box load when the grid power reaches the set value. After the power grid returns to normal, the crew needs to go to the cold box distribution board and manually close the switch to restore the cold box power supply. In order to cope with IMO's CII regulations, most shipowners currently only configure cold box power monitoring, which can only reflect the annual total energy consumption of the cold box power.

[0004] It can be seen that there are several problems in the current allocation of cold box loads on large container ships: (1) When the ship is sailing normally and the cold box is loaded on the grid, when the intermittent load on the ship fluctuates or high-power load needs to be connected to the grid, the standby generator needs to be started and closed so that the grid can bear the load, which increases fuel consumption and emissions. The increase in fuel consumption and emissions directly raises operating costs.

[0005] (2) Large container ships transport a large number of refrigerated containers. Four sets of refrigerated box distribution boards are usually installed for power supply, distributed in four areas at the bow and stern. The addition and subtraction of the refrigerated box load requires the crew to manually adjust the load by opening and closing the switch. Each refrigerated box distribution box 4.3 power switch is manually closed. The refrigerated box distribution boards are distributed in multiple locations at the bow and stern. The operation is cumbersome, time-consuming and labor-intensive. In addition, in order to cope with the sudden load fluctuations of the power grid, it is necessary to connect the grid-connected standby generator to meet the use requirements of the ship's power grid, which increases fuel consumption and emissions.

[0006] (3) Conventional cold box power monitoring can only reflect the annual total energy consumption of the cold box power, but cannot reflect energy-saving and emission reduction measures and energy-saving effects. The carbon intensity factor CII rating is too low. Summary of the invention

[0007] The purpose of the present invention is to overcome the above-mentioned shortcomings, solve the problems of inconvenient operation of existing cold box load adjustment, increased energy consumption due to frequent use of standby generators, and too low carbon intensity factor CII rating, and provide a soft tripping system for ship cold box load and a method of using the same. Under the premise of meeting the normal operating conditions of the ship power grid, the system improves the degree of intelligence, simplifies the operation, reduces fuel consumption and emissions, meets the new decarbonization regulations, and is more competitive in the market.

[0008] The object of the present invention is achieved in that: A soft tripping system for ship cold box loads, comprising a power management workstation and multiple sets of cold box switchboards, wherein the power management workstation is arranged in a centralized control room, and at least two sets of cold box switchboards are arranged and distributed in the bow and stern areas; The power management workstation includes a main PLC module and a PC module. The PC module is connected to the loading computer and the cargo hold fan control system respectively. The actual cold box loading information on the ship is collected through communication with the loading computer. The fan operation status and the control authority for starting and stopping the fan are obtained through communication with the cargo hold fan control system. The main PLC module is connected to a plurality of sub-PLC modules through optical fibers. The sub-PLC modules correspond to the cold box distribution board one by one and are arranged inside the cold box distribution board. The relevant information is directly collected inside the distribution board, and the signal is input to the power management workstation in the control room through the optical fiber ring network. Each sub-PLC module is provided with an analog receiving module and an input and output module. The cold box power distribution board is provided with a plurality of refrigerated power distribution box supply switches, and the refrigerated power distribution box supply switches are provided with a power monitoring module, and the power monitoring module is connected to the analog quantity receiving module of the sub-PLC module in the cold box power distribution board, and the real-time power signal is connected to the analog quantity signal module of the PLC in the power distribution board; The refrigerated distribution box supply switch is configured with an electrical operation function, and the refrigerated distribution box supply switch is connected to the input and output module of the sub-PLC module in the cold box distribution board through the electrical operation function, and the control signal and status signal of the refrigerated distribution box supply switch are connected to the input and output module of the PLC in the power board.

[0009] Furthermore, there are four sets of cold box power distribution boards, which are respectively arranged in the port bow transformer room, the starboard bow transformer room, the port aft engine room second deck and the starboard aft engine room second deck.

[0010] Furthermore, the main PLC module is connected to a plurality of sub-PLC modules via optical fibers.

[0011] Furthermore, each cold box switchboard is connected to a cold box transformer, and the cold box transformer is connected to a busbar in the medium voltage switchboard room.

[0012] Furthermore, the busbar is connected to a plurality of generators.

[0013] Furthermore, each refrigerated distribution box supply switch is connected to an independent distribution box.

[0014] Furthermore, the power monitoring module is inserted and arranged on the supply switch of the refrigerated distribution box.

[0015] A method for using a soft tripping system for a ship cold box load, comprising the following contents: S1, soft tripping priority calculation method: S1.1. Based on the average load calculation of each refrigerated distribution box, the RP with the lowest average load of each refrigerated distribution box will have the highest priority; S1.2. Use the following formula to calculate the load index: Load index = total number of cold box packing / average load of distribution box (KW) * (1+100*number of extra-large cold boxes), The average load of the distribution box is defined as the average load within 20 minutes. The distribution box with the largest load index has the highest priority; S2. Calculation method of soft tripping load: S2.1. Calculate the number of distribution boxes N that need to be disconnected; In addition to the priority level, when the "Load Soft Trip" command is activated, the "Power to Trip" will be used to determine how many cold box distribution boxes are disconnected from the power supply; The power of each cargo hold fan is fixed. When calculating the cargo hold fan load, only the running fans need to be considered. The cargo hold fan load is the first choice under any priority. S2.2, gradually disconnect from the grid according to the priority order calculated by the soft tripping priority; Tripping order: cargo hold fan → distribution box priority level 1 → distribution box priority level 2 ... → distribution box priority level N; S2.3. After the grid instruction "power to be tripped" is eliminated, the soft trip loads are loaded in reverse step by step according to the priority order to restore normal power supply.

[0016] S3. Software compilation and historical record storage implementation: S3.1. Prepare a logic program based on the collected signals and the defined calculation method; S3.2, the generator power before and after soft tripping is recorded in the computer; S3.3, cold box power before and after soft tripping, recorded in the computer; S3.4. Generate energy consumption data summary report based on power record curve and draw conclusion on energy saving effect.

[0017] Furthermore, the number of distribution boxes that need to be disconnected in step S2.1 is calculated based on the following two judgment conditions: ∑ "Power of N distribution boxes (KW)" + "Power of cargo hold fan (KW)" > "Power to be tripped", ∑ “N-1 distribution box power (KW)” + “cargo hold fan power (KW)” < “power to be tripped”.

[0018] Furthermore, in step S1.2, the distribution boxes with the following conditions will be proposed from the priority calculation: the power switch is in manual or local state / the power switch is in alarm state / the power monitoring module fails / the distribution box does not supply power to the cold box.

[0019] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a soft tripping system for ship cold box load and a method for using the system. The system adopts a distributed module design method, and can manually and automatically allocate the cold box load at a power management workstation 1 to reduce the working conditions of using a standby generator, thereby achieving energy saving and emission reduction effects. The system can also directly generate an annual total energy consumption report for the cold box power and an energy saving effect report, thereby improving the carbon intensity factor CII rating.

[0020] The present invention improves the intelligence level, and the cold box load allocation work can be completed at the workstation, which makes the operation simpler and more convenient; the present invention significantly improves the energy-saving and emission reduction effects, saves costs, and improves the economic benefits of ship operation; the present invention meets the IMOCII regulations, improves the carbon intensity factor CII rating, and reduces the payable carbon tax benchmark. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the system structure of the present invention.

[0022] in: Power management workstation 1, main PLC module 1.1, PC module 1.2, sub-PLC module 1.3, loading computer 2, cargo hold fan control system 3, No. 1 cold box distribution board 4, refrigerated distribution box supply switch 4.1, power monitoring module 4.2, distribution box 4.3, No. 2 cold box distribution board 5, No. 3 cold box distribution board 6, No. 4 cold box distribution board 7, No. 1 cold box transformer 8, No. 2 cold box transformer 9, No. 3 cold box transformer 10, No. 4 cold box transformer 11, No. 1 generator 12, No. 2 generator 13, No. 3 generator 14, No. 4 generator 15. DETAILED DESCRIPTION

[0023] In order to better understand the technical solution of the present invention, the following will be described in detail in conjunction with the relevant illustrations. It should be understood that the following specific embodiments are not intended to limit the specific implementation of the technical solution of the present invention, and are only implementations that can be adopted by the technical solution of the present invention. It should be noted that the description of the positional relationship of each component in this article, such as component A being located above component B, is based on the description of the relative positions of the components in the illustration, and is not intended to limit the actual positional relationship of the components. Example 1

[0024] See also Figure 1 , Figure 1 Draw a schematic diagram of the system structure of a soft tripping system for a ship's cold box load of the present invention. As shown in the figure, a soft tripping system for a ship's cold box load of the present invention includes a power management workstation 1 and four sets of cold box distribution boards. The power management workstation 1 is arranged in the centralized control room. The four sets of cold box distribution boards are cold box distribution board No. 1 4, cold box distribution board No. 2 5, cold box distribution board No. 3 6 and cold box distribution board No. 4 7. Cold box distribution board No. 1 4 is arranged in the port bow transformer room, cold box distribution board No. 2 5 is arranged in the starboard bow transformer room, cold box distribution board No. 3 6 is arranged on the second deck of the port rear engine room, and cold box distribution board No. 4 7 is arranged on the second deck of the starboard rear engine room.

[0025] The power management workstation 1 includes a main PLC module 1.1 and a PC module 1.2. The PC module 1.2 is connected to the loading computer 2 and the cargo hold fan control system 3 respectively. Through communication with the loading computer 2, the actual refrigerated container loading information on the ship is collected, including refrigerated container loading information such as container position and size. Through communication with the cargo hold fan control system 3, the fan operating status and the control authority for starting and stopping the fan are obtained.

[0026] The main PLC module 1.1 is connected to four sub-PLC modules 1.3 through optical fibers. The four sub-PLC modules 1.3 are respectively arranged inside the No. 1 cold box distribution board 4, the No. 2 cold box distribution board 5, the No. 3 cold box distribution board 6 and the No. 4 cold box distribution board 7. Relevant information is directly collected inside the distribution board, and the signal is input to the power management workstation 1 in the control room through the optical fiber ring network; each sub-PLC module 1.3 is provided with an analog receiving module and an input and output module.

[0027] The No. 1 cold box distribution board 4 is connected to the No. 1 cold box transformer 8, the No. 2 cold box distribution board 5 is connected to the No. 2 cold box transformer 9, the No. 3 cold box distribution board 6 is connected to the No. 3 cold box transformer 10, and the No. 4 cold box distribution board 7 is connected to the No. 4 cold box transformer 11; the No. 1 cold box transformer 8 and the No. 3 cold box transformer 10 are respectively connected to bus A, the No. 2 cold box transformer 9 and the No. 4 cold box transformer 11 are respectively connected to bus B, bus A and bus B are arranged in the medium voltage distribution board room, bus A is also connected to generator No. 12 and generator No. 2 13, and bus B is also connected to generator No. 3 14 and generator No. 4 15.

[0028] The No. 1 cold box distribution board 4 is provided with a plurality of refrigerated distribution box supply switches 4.1, each refrigerated distribution box supply switch 4.1 is connected to an independent distribution box 4.3, and a power monitoring module 4.2 is inserted on the refrigerated distribution box supply switch 4.1, and the power monitoring module 4.2 is connected to the analog quantity receiving module of the sub-PLC module 1.3 in the No. 1 cold box distribution board 4, and the real-time power signal is connected to the analog quantity signal module of the PLC in the distribution board; The refrigerated distribution box supply switch 4.1 is equipped with an electric operation function, and the refrigerated distribution box supply switch 4.1 is connected to the input and output module of the sub-PLC module 1.3 in the No. 1 cold box distribution board 4 through the electric operation function, and the control signal and status signal of the refrigerated distribution box supply switch 4.1 are connected to the input and output module of the PLC in the power board.

[0029] The internal structures of the No. 2 cold box distribution board 5 , the No. 3 cold box distribution board 6 and the No. 4 cold box distribution board 7 are the same as the above-mentioned structure of the No. 1 cold box distribution board 4 .

[0030] A method for using a soft tripping system for a ship cold box load of the present invention comprises the following contents: S1, soft tripping priority calculation method: S1.1. Calculated based on the average load of each refrigerated distribution box, up to 10 priorities; the RP with the lowest average load of each refrigerated distribution box will have the highest priority (lowest value); S1.2: When loading extra-large cold boxes, it is necessary to calculate the load index of the distribution box. Considering that each distribution box may be loaded with extra-large cold boxes, the following formula is used to calculate the load index: Load index = total number of cold box packing / average load of distribution box (KW) * (1+100*number of extra-large cold boxes), The average load of the distribution box is defined as the average load within 20 minutes. The distributor with the highest load index has the highest priority.

[0031] S1.3. The distribution boxes with the following conditions will be included in the priority calculation: the power switch is in manual or local state / the power switch is in alarm state / the power monitoring module is faulty / the distribution box does not supply power to the cold box; S2. Calculation method of soft tripping load: S2.1. In addition to the priority, when the "load soft trip" command is activated, the "to-trip power" will be used to determine how many cold box distribution boxes are disconnected from the power supply; The power of each cargo hold fan is fixed. When calculating the cargo hold fan load, only the running fans need to be considered. The cargo hold fan load is the first choice under any priority. The number of distribution boxes that need to be disconnected is calculated based on the following two criteria: (1) ∑ "N distribution box power (kW)" + "cargo hold fan power (kW)" > "power to be tripped", (2) ∑ “N-1 distribution box power (kW)” + “cargo hold fan power (kW)” < “power to be tripped”; The number of distribution boxes N that need to be disconnected is calculated, and they are gradually disconnected from the power grid in the order of priority calculated according to the soft tripping priority; S2.2, tripping sequence: cargo hold fan → distribution box priority level 1 → distribution box priority level 2 ... → distribution box priority level N; S2.3. After the grid instruction "power to be tripped" is eliminated, the soft trip loads are loaded in reverse step by step according to the priority order to restore normal power supply.

[0032] S3. Software compilation and historical record storage implementation: S3.1. Prepare a logic program based on the collected signals and the defined calculation method; S3.2, the generator power before and after soft tripping is recorded in the computer; S3.3, cold box power before and after soft tripping, recorded in the computer; S3.4. Generate energy consumption data summary report based on power record curve and draw conclusion on energy saving effect.

[0033] Working principle: The present invention provides a soft tripping system for ship cold box loads. The system adopts a distributed module design method to distribute the PLC modules of power management to four sets of cold box distribution boards as needed, directly collect relevant information inside the distribution boards, and input the signals to the power management workstation 1 in the control room through an optical fiber ring network. The design scheme can save a lot of signal cables.

[0034] The acquisition of control and monitoring signals of the present invention: a. Power signal acquisition: Using the plug-in design principle, the power monitoring module is inserted into the power switch of each cold box distribution box inside the four cold box distribution boards. And it is connected to the analog receiving module of the PLC inside the distribution board.

[0035] b. Switch control signal acquisition: All refrigerated distribution boxes in the distribution boards supply switches with electrical operation functions, and the control and status signals are connected to the input and output modules of the PLC in the distribution board.

[0036] c. Collection of refrigerated container loading information: By communicating with the loading computer 2, the actual refrigerated container loading information on board is obtained, including the placement and size of the refrigerated container.

[0037] d. Cargo hold fan information collection: By communicating with the cargo hold fan control system 3, the fan operating status and the control authority for starting and stopping the fan are obtained.

[0038] The above are only specific application examples of the present invention and do not constitute any limitation on the protection scope of the present invention. Any technical solution formed by equivalent transformation or equivalent replacement shall fall within the protection scope of the present invention.

Claims

1. A soft tripping system for ship cold box load, characterized in that: It comprises a power management workstation (1) and a plurality of cold box switchboards, wherein the power management workstation (1) is arranged in a centralized control room, and at least two cold box switchboards are arranged and distributed in the bow and stern areas; The power management workstation (1) comprises a main PLC module 1.1 () and a PC module (1.2), wherein the PC module (1.2) is connected to a loading computer (2) and a cargo hold fan control system (3) respectively, and collects actual cold box loading information on board through communication with the loading computer (2), and obtains fan operation status and fan start and stop control authority through communication with the cargo hold fan control system (3); the main PLC module (1.1) is connected to a plurality of sub-PLC modules (1.3), and the sub-PLC modules (1.3) correspond to the cold box distribution board one by one, are arranged inside the cold box distribution board, directly collect relevant information inside the distribution board, and input signals to the power management workstation (1) in the control room through an optical fiber ring network; each sub-PLC module (1.3) is provided with an analog quantity receiving module and an input and output module; The cold box power distribution board is provided with a plurality of refrigerated power distribution box supply switches (4.1), and the refrigerated power distribution box supply switches (4.1) are provided with a power monitoring module (4.2). The power monitoring module (4.2) is connected to an analog quantity receiving module of a sub-PLC module (1.3) in the cold box power distribution board, and connects a real-time power signal to an analog quantity signal module of the PLC in the power distribution board; The refrigerated distribution box supply switch (4.1) is equipped with an electric operation function. The refrigerated distribution box supply switch (4.1) is connected to the input and output module of the sub-PLC module (1.3) in the cold box distribution board through the electric operation function, and the control signal and status signal of the refrigerated distribution box supply switch (4.1) are connected to the input and output module of the PLC in the power board.

2. A soft tripping system for ship cold box load according to claim 1, characterized in that: The cold box power distribution board is provided with four sets, which are respectively arranged in the port bow transformer room, the starboard bow transformer room, the port aft engine room second deck and the starboard aft engine room second deck.

3. A soft tripping system method for ship cold box load according to claim 1, characterized in that: The main PLC module (1.1) is connected to a plurality of sub-PLC modules (1.3) via optical fibers.

4. A soft tripping system for ship cold box load according to claim 1, characterized in that: Each cold box switchboard is connected to a cold box transformer, which is connected to the busbar in the medium voltage switchboard room.

5. A soft tripping system for ship cold box load according to claim 4, characterized in that: The busbar connects a plurality of generators.

6. A soft tripping system for ship cold box load according to claim 1, characterized in that: Each refrigerated distribution box supply switch (4.1) is connected to an independent distribution box (4.3).

7. A soft tripping system for ship cold box load according to claim 1, characterized in that: The power monitoring module (4.2) is inserted and arranged on the supply switch (4.1) of the refrigerated power distribution box.

8. A method for using the soft release system for ship cold box load according to claim 1, characterized in that: Includes the following: S1, soft tripping priority calculation method: S1.

1. Based on the average load calculation of each refrigerated distribution box, the RP with the lowest average load of each refrigerated distribution box will have the highest priority; S1.

2. Use the following formula to calculate the load index: Load index = total number of cold box packing / average load of distribution box (KW) * (1+100*number of extra-large cold boxes), The average load of the distribution box is defined as the average load within 20 minutes. The distribution box with the largest load index has the highest priority; S2. Calculation method of soft tripping load: S2.

1. Calculate the number of distribution boxes N that need to be disconnected; In addition to the priority, when the "load soft trip" command is activated, the "to-trip power" will be used to determine how many cold box distribution boxes are disconnected from the power supply; The power of each cargo hold fan is fixed. When calculating the cargo hold fan load, only the running fans need to be considered. The cargo hold fan load is the first choice under any priority. S2.2, gradually disconnect from the grid according to the priority order calculated by the soft tripping priority; Tripping order: cargo hold fan → distribution box priority level 1 → distribution box priority level 2 ... → distribution box priority level N; S2.3, after the grid instruction "power to be tripped" is eliminated, the soft trip load is loaded in reverse order step by step according to the priority order to restore normal power supply; S3. Software compilation and historical record storage implementation: S3.

1. Prepare a logic program based on the collected signals and the defined calculation method; S3.2, the generator power before and after soft tripping is recorded in the computer; S3.3, the cold box power before and after soft tripping is recorded in the computer; S3.

4. Generate energy consumption data summary report based on power record curve and draw conclusion on energy saving effect.

9. The method for using the soft tripping system of a ship cold box load according to claim 8, characterized in that: The number of distribution boxes that need to be disconnected in step S2.1 is calculated based on the following two judgment conditions: ∑"N distribution box power (KW)" + "cargo hold fan power (KW)" > "to be tripped power", ∑"N-1 distribution box power (KW)" + "cargo hold fan power (KW)" < "power to be tripped".

10. The method for using the soft tripping system of a ship cold box load according to claim 8, characterized in that: In step S1.2, the distribution boxes with the following conditions will be proposed from the priority calculation: the power switch is in manual or local state / the power switch is in alarm state / the power monitoring module fails / the distribution box does not supply power to the cold box.

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